int leastInterval(vector<char>& tasks, int n) {

unordered_map<char, int> taskFreq;

for (char task : tasks) {

taskFreq[task]++;

}

priority_queue<pair<int, char>> pQ;

for (pair<char, int> taskCount : taskFreq) {

pQ.push({taskCount.second, taskCount.first});

}

int interval = 0;

int cycle = n + 1;

while(!pQ.empty()) {

int tasks = 0;

vector<pair<int, char>> tmp;

for(int i = 0; i < cycle; i++) {

if(!pQ.empty()) {

tmp.push_back(pQ.top());

pQ.pop();

tasks++;

}

}

for(auto task : tmp) {

if(--task.first) {

pQ.push(task);

}

}

interval += !pQ.empty() ? cycle : tasks;

}

return interval;

}